Barnabas Health and Robert Wood Johnson Health System have finalized their plans to merge, creating the largest hospital chain in the state stretching from Essex County to the Jersey shore, the hospitals announced Tuesday. The new nonprofit entity will be known as RWJ Barnabas Health.

Health insurers and some consumer healthcare advocates say mergers often drive up the costs of health care because they are able to command more generous reimbursement rates.

When the Attorney General's Office is finished with its review, assuring that the community benefits and services the hospital systems provided separately will continue as one merged entity, RJW Barnabas Health will be immense. Together, they have $4.5 billion in revenues, 260,000 inpatient admissions, 2 million outpatient visits, nearly 700,000 emergency department visits, 23,000 births, nearly 30,000 employees, 9,000 physicians, and 1,000 residents and interns, according to the announcement.